It is relatively well known that silver ions (Ag+) in measured doses are toxic to lower life forms such as bacteria but are non-toxic to humans. In fact there is evidence available that silver provides significant benefits to the functioning of the human body and offers particular benefits to the immune system. Various types of apparatus are presently available for dosing water with silver ions in order to take advantage of the bactericide effects of silver and typically such apparatuses include a flow switch which activates a silver ion generator upon a person turning on a tap for a glass of water. Generally, apparatuses of this type have been used only in reticulated water systems, for example, where town water is connected and is already relatively clean and reasonably safe.
The steady growth of tourism in outback areas has placed an undesirable burden on government authorities to provide safe drinking and bathing water in such areas for the benefit of tourists and holiday makers. However, the provision of such facilities decreases the appeal of the outback and the ability of tourists and holiday makers to camp where they like. Moreover any facilities provided could possibly be destroyed or rendered ineffective by vandals. Additionally there are many areas which are so little used and so remote that government authorities are unable to provide and maintain the necessary facilities particularly in developing nations and jungle areas. Furthermore, even if presently available apparatus were to be used in remote areas, in some cases they do not control the growth of harmful bacteria downstream of the apparatus to a satisfactory extent.
One object of the present invention is to provide water treatment apparatus which controls or at least inhibits the growth of harmful bacteria downstream of the apparatus and which can be used in outback areas and/or with reticulated water supplies to improve water quality or at least decrease the possibility of harmful bacteria being consumed. Another object is to provide portable water treatment apparatus which will allow holiday makers and others, especially those with four wheel drive vehicles, to sterilise and filter water from streams, water holes, dams and the like thus converting it to potable water for drinking and washing. Another object is to provide an improved flow switch which can be used for activating a silver ion generator in water treatment apparatus of the type herein described.